Askar FRA400C Quintuplet Refractor

HIGH QUALITY MULTIFUNCTION ASTROGRAPH

Specifications

• Aperture diameter: 72 mm
• Focal length: 400 mm
• Focal ratio: f/5.6
• Objective: quintuplet air spaced APO with dual ED glass
• Supported format: 44 mm
• Aperture blades: 17 pieces
• Graded aperture: f/5.6 to f/22
• Minimum focusing distance: 5 m
• Focusing mode: manual focus
• Filter thread diameter: M82
• Total length: 370 mm (with dew shield) ; 420 mm (without dew shield)
• Tube weight: 2.68 kg
• Total weight with handle and dovetail: 3.18 kg
• Rear adapter: M72 / M54 / M48 (with M48×0.75 filter thread)
• Rear connection distance: supported range 50–60 mm (recommended connection length 55 mm)

Standard package contents

• 1.25″ / 2″ adapter
• Manual

HIGH QUALITY MULTIFUNCTION ASTROGRAPH
Astrophotography / Daily photography / Visual observation

ED QUINTUPLET REFRACTOR
The FRA400C features a 72 mm aperture, a 400 mm focal length, and a focal ratio of f/5.6. It uses a quintuplet optical design including two ED lenses, covering a full frame image circle of 44 mm.

INTEGRATED FIELD CORRECTION DESIGN
The FRA400C optical structure is identical to the FRA400, based on a Petzval architecture. It eliminates any need for backfocus calculation. With a connection range between 50 mm and 60 mm, the user can image directly once the OTA is focused.

VERSATILE APPLICATIONS
The FRA400C is mechanically optimized for different uses. It can be used for astrophotography, standard photography and visual observation.

RETRACTABLE DEW SHIELD
The FRA400C is equipped with a retractable dew shield with an integrated engraved ring.

ADJUSTABLE APERTURE
The FRA400C aperture ranges from f/22 to f/5.6 with scale markings on the tube for step adjustment, preventing accidental changes and preserving settings.

INTEGRATED HELICOIDAL FOCUSING
Single speed helicoidal focusing mechanism with locking screw for simple operation. It uses MXL-type synchronous gears compatible with MXL belts for motorized focusers. Its adjustable damping system improves focusing stability in astrophotography while offering faster focusing in daily use.

EXTENDED MULTI-MOUNT QUICK RELEASE TUBE RING
The FRA400C features an upgraded ring with four sets of M4 and M6 threads for mounting various accessories. Two finder bases are included for attaching different astronomical equipment.

DOVETAIL PLATE
Standard 290 mm Vixen style dovetail plate for smooth installation and handling.

ROTATION
The optical assembly can be rotated to adjust framing angle during imaging.

FOUR PIECE PHOTOGRAPHIC ADAPTER
The rear of the FRA400C includes a four piece photographic adapter set (M72-M54-M48) with an internal 2″ filter thread on the M48 adapter.

VISUAL OBSERVATION ADAPTERS
Includes 2″ and 1.25″ eyepiece adapters for visual use.

FRA400C FULL FRAME REDUCER (OPTIONAL)
The optional FRA400C 0.7× reducer shortens focal length to 280 mm and focal ratio to f/3.9 while supporting a 44 mm full frame image circle.
Note: not compatible with FRA400.

Spécifications

• Diamètre d’ouverture : 72 mm
• Longueur focale : 400 mm
• Rapport focal : f/5.6
• Objectif : quintuplet APO espacé air avec double verre ED
• Format supporté : 44 mm
• Lamelles de diaphragme : 17 pièces
• Ouverture graduée : f/5.6 à f/22
• Distance minimale de mise au point : 5 m
• Mode de mise au point : mise au point manuelle
• Diamètre du filetage filtre : M82
• Longueur totale : 370 mm (avec pare-buée) ; 420 mm (sans pare-buée)
• Poids du tube : 2,68 kg
• Poids total avec poignée et queue d’aronde : 3,18 kg
• Adaptateur arrière : M72 / M54 / M48 (avec filetage filtre M48×0,75)
• Distance de connexion arrière : plage supportée 50–60 mm (longueur recommandée 55 mm)

Contenu du pack standard

• Adaptateur 1,25″ / 2″
• Manuel